Abrasive brush



Sept. 22, 1970 E. A. STEIN ABRASIVE BRUSH Filed NOV. 12, 1968 SEGMENTB V SEGMENTA FIE.Z

ED -iNV NT R GAR .1 Em 7/ ATTORNEY United States Patent Ofiice 3,529,385 Patented Sept. 22, 1970 3,529,385 ABRASIVE BRUSH Edgar A. Stein, Troy, N.Y., assignor to Norton Company, Troy, N.Y., a corporation of Massachusetts Filed Nov. 12, 1968, Serl'No. 774,976 Int. Cl. B24d 11/00 US. Cl. 51--394 ABSTRACT F THE DISCLOSURE A polishing brush having a plurality of relatively long edge-mounted strips of a lofty, compressible, resilient nonwoven polishing media secured to and extending from the core to the outer periphery of a backing member and having interspersed near the outer periphery of such member a plurality of shorter length strips of the same material sufficient to produce at least the same density of polishing media at the outer periphery as exists at the core.

FIELD OF INVENTION The present invention relates to the field of polishing brushes and in particular to such brushes for use as a surface cleaning or treating device.

PRIOR ART Floor and similar surface-treating brushes have heretofore been made from lofty non-woven material (with or without abrasive) as an improvement over the older bristle-type brus'hes. Such polishing brushes have generally been of two configurations-a long strip accordion-pleated and. secured on edge about the periphery of a backing member or a molded or compressed mass formed by winding a web of the material on a mandrel and adhesively securing adjacent convolutions one to the other to form a convolute solid. This solid or a section thereof was then adhered in ring form to the face of a backing member. These brushes suffer from lack of conformity to irregularities in the floor and to extreme variations in density or hardness, particularly when wide face widths are used.

SUMMARY The device of the present invention provides a structure which is resilient, conformable to a surface and which alfords rapid and chatter-free cleaning action on a surface. When the strips are radially positioned on the backing, the increasingly smaller diameter as the center or core of the backing is approached, limits the number of strips which can be used. This means also that a much higher density of polishing material exists at the center than at the outer periphery. By inserting between the longer strips or between groups of the longer strips, shorter strips of the same material and securing these to the backing adjacent the outer periphery, this density gradient is substantially eliminated or, as is the case with brushes for fiooruse, can be reversed to give a higher density at the outer periphery. The shorter strips will vary in length, depending upon the length of the longer strips and the density uniformity required. The exact number and location of these shorter strips will also'vary, depending upon the density desired. In general, the shorter strips will range from 25% up to 60% of the length of the longer strips and will be present in numbers equal to the number of the longer strips or at least equal to 50% of the number of the longer strips. The limitation on the length and number of the strips will in all events be such as to provide a density at the outer periphery at least equal to the density at the core of the supporting member. While the thickness of the strips may and will vary somewhat, due to the nature of the material, in the preferred version the thickness of the shorter strips will generally be the 4 Claims same as that of the longer strips. Preferably, each strip is individually anchored to the backing member. The longer strips are preferably rectangular in form with one of the longer sides of each stripbeing anchored in radially disposed manner to a rigid or semi-rigid circular back-up member.

DRAWINGS FIG. 1 is a schematic plan view of the device of the present invention showing the intermixed long and short strips.

FIG. 2 shows a segment of a typical device with and without the added shorter strips to provide a pictorial comparison.

Referring now to FIG. 1, the brush 10 is made up of a circular rigid backing or support member 11 having a central opening or core 12. Extending radially outward from the core 12 to the outer periphery 13 of the support member 11 are a plurality of long resilient, compressible non-woven polishing strips 14. These are preferably formed of a lofty non-woven synthetic filament web impregnated'with adhesively-secured abrasive, as illustrated in US. 3,020,139 to Camp et al., although in many instances the same material or similar material without abrasive may be used. In the version illustrated, shorter strips 15 of this same material are alternated between strips 14 and adjacent the outer periphery 13. Since the material is compressible, it can be seen that insertion of the strips 15 cause the density of the outer portion of the device to at least equal the density of the interior portion adjacent the core 12.

As is more clearly shown in FIG. 2, segments of brushes are shown side-by-side. Segment A shows a brush made only with long equal length strips 21 adhered on edge 22 to backing member 23 and extending from the central core or opening 24 to the outer periphery 25 of member 23. Wide gaps 26 will inherently occur in such construction and a count of the number of strips per unit of length along the arc of the periphery as contrasted with the count along the arc of the inner core clearly shows the density gradient that the present invention is designed to overcome. Segment B shows the segment A with the addition of shorter strips 27 intermediate the longer strips 21. A count of the strips per unit of arc length here clearly shows that the outer peripheral density in the case of the present construction is at least equal to and, in this instance, two times greater than the density at the inner core 24.

The shorter strips need not be of uniform length, although in the preferred construction they usually are. Likewise, a variety of lengths may be employed in the same brush, if desired, in order to vary the density gradient to a desired degree. Likewise, the strips may be formed from folded or pleated materials, if desired, and in such instances, although the strips are attached to one another in whole or in part, the action of the strips is similar to that of individual strips, i.e., the arms of the folded or pleated strips are free of attachment to adjacent arms and hence free to flex and conform individually to the surface being treated. The requirement in each instance is, however, that the density of the polishing media pres" ent in individual flexible strips be at least as great at the outer periphery as the density at the inner core.

The devices of this invention find particular use in the cleaning or stripping of wax from floor surfaces but may be used in such diverse applications as automotive sanding or cleaning, sanding or cleaning of industrial parts and the like.

What I claim is as follows:

1. A polishing brush comprising:

(a) a base member having a central core opening and an outer peripheral portion;

(b) a plurality of radially-extending resilient and compressible polishing strips extending from said core opening to the outer edge of said peripheral portion and being secured only along the edge of each such strip so extending to said base member; and

(c) a second plurality of radially-extending resilient and compressible polishing strips so interspersed between said strips forming said first plurality as to extend from said outer periphery inwardly towards but to terminate short of said central core opening, said second plurality of strips being secured along said extending edge to said base member and providing a density of polishing strips adjacent said outer periphery at least equal to the density of polishing strips adjacent said core opening.

2. A polishing brush, as in claim 1, wherein said second plurality of polishing strips each comprise a nonwoven, high loft synthetic filament Web.

3. A polishing brush, as in claim 1, wherein said resil References Cited UNITED STATES PATENTS 2,334,642 11/1943 Moore 5l356 3,181,193 5/1965 Nobles et a1 15-114 FOREIGN PATENTS 914,315 1/1963 Great Britain.

OTHELL M. SIMPSON, Primary Examiner U.S. Cl. X.R. 15-230.16 

